Heidi Montag and husband Spencer Pratt share 4-year-old Gunner Stone together
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Heidi Montag and Spencer Pratt attend WE tv Celebrates the 100th Episode of the "Marriage Boot Camp"
Credit: Presley Ann/Getty

Heidi Montag is getting honest with her fans. 

The Hills: New Beginnings star, 35, shared a candid message on Instagram on Tuesday about trying for baby number two with husband and fellow reality star Spencer Pratt, posting a series of photos with their 4-year-old son, Gunner Stone. 

"So thankful for my angel," Montag captioned the collection of sweet snaps of herself and Gunner. "I never thought it would be so hard trying to have another. I am trusting God's plan and if we only have one I am so thankful for this miracle!"

In the photos, Montag and her adorable son are twinning in casual baseball hats and sunglasses, snuggling and smiling while sitting on a large rock near the ocean. The reality star also posted a boomerang of the pair at the water's edge on her Instagram Story.

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Over the last year, Montag has been open with her fans about her and Pratt's desire to have another child.

In August, the Speidi Podcast host posted a YouTube video that gave fans an inside look as she underwent a hysteroscopic polypectomy procedure, where non-cancerous uterine polyps are removed.

"I was feeling nervous last night about it, but I'm excited today," Montag said on her vlog. "And I'm hoping that the surgery works and that this is the only reason I haven't been able to get pregnant."

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"Hopefully after this, I can get pregnant right away," she continued, adding, "Obviously, I think it's the perfect timing and meant to be. And so thankful I didn't have other problems and complications from this."

In May last year, Montag and Pratt, 38, appeared on PeopleTV's Reality Check to talk about trying for another child, revealing that they are "still working as hard as possible at it" and that they never thought it would "be this challenging."

"We tried different lifestyles and everything we could think of," Pratt explained. "So yeah, we're still working on that one."